Tool feed control



May 29, 1962 F. R. wHlTcoMB TooL. FEED CONTROL Filed Nov. 2, 1960 3,036,409 TOOL FEED CONTROL Forrest R. Whitcomb, 152 Chandler St., Worcester, Mass. Filed Nov. 2, 1961i, Ser. No. 66,869 7 Claims. (Cl. 51-99) This invention relates to a new and improved tool feed control, and the principal object of the invention is to provide a movable tool which is completely under control of the operator as to the motion thereof relative to a workpiece, but at the same time is power-operated in the travel thereof and which is controlled by a new and improved mechanism to ensure that the travel of the tool is constant and is not affected by climb `or resistance of the action of the cutting tool due to friction relative to the workpiece.

it is well known that when for instance a swing-type of rotary mounted tool is brought into contact with a workpiece, it tends to travel or climb in the direction of the rotation of the tool due to frictional engagement of the tool with the work. For instance, if a buing wheel which is rapidly rotated and mounted on a lfreely movable swing, is brought into contact with the surface of a workpiece to polish the same, the tool if rotating toward the operator will in and of itself have a very delinite and dangerous motion toward the operator, and of course the converse is true. This invention provides means overcoming this diiliculty and controlling the feed of the tool positively and accurately by a very simple and eicient mechanism.

The invention further relates to arrangements land combinations of parts which will -be hereinafter described and more particularly set forth in the appended claims.

Reference is to be had to the accompanying drawings, in which FIG. l is a view in side elevation showing the invention;

FIG. 2 is a top plan view of Ia portion thereof;

FIG. 3 is a fragmentary end elevation, looking in the direction of arrow 3 in FIG. l; and

FlG. 4 is a diagrammatic view showing a control Valve.

In carrying out the present invention, the same is shown as being applied to a swing-type of tool which serves as a mount for a bufling wheel adapted -to polish a workpiece which may be mounted on a work-table rotatably mounted in turn on a rectilinearly movable table 12. These work-supports may conveniently be controlled and locked as desired. The members 10 and l2 may be mounted in any way desired as on a framework 16 of more or less usual character, and it will be seen that the operator can position the work where desired.

in order to provide for a support for the present tool, there is provided a base plate 18 to the rear of the framework 16 and on this plate there may be mounted a motor 20 and a vblock or the like at 22. which provides a rotary mounting for a swing shaft. On the swing shaft there is mounted `a standard 24 which in the case shown herein is conveniently provided by a pair of rods or tubes mounted to swing on the shaft located in the Iblock 22 as for instance by a bearing or the like which is indicated at 26.

The motor drives a pulley concealed in a guard 28 and this pulley may drive a belt, etc., also concealed within the guard 28 more or less as usual.

At the upper end of the standard 24, there is provided a convenient housing 30 and this housing carries a jack shaft driven by the motor 20 which transfers the energy therefrom to a pulley mounted in another swing-like housing 32 again in more or less the usual manner. The guard 32 also conceals a pulley at the forward end thereof `for driving the tool 34 which in this case is shown as a butfing wheel.

3,036,409 Patented May 29, 1962 The housing at 30 may conveniently provide a support for a pair of forwardly-extending rods or tubes 36 and at their outer ends these rods or tubes provide a support for a bearing or housing which is indicated at 38. The shaft directly driving the tool 34 is housed therein so that it will `be seen that complete swinging tool -type of device is power-driven. A handle generally indicated at 40 is provided by which the operator may swing the devicev in order to draw the tool down into contact with the work on the table 10 and also to move the tool 34 backand-forth across the surface of the work.

rthe handle at 46, however, in this invention is not mounted directly in fixed relation to the bearing housing at 3S but instead is mounted on a rod 42 which has a motion relative to said housing 38 land to the rod support 36 so that when handle 40 is grasped land pulled toward the operator, it has a slight motion forwardly relative to the tool.

The handle rod 42 is associated with a valve 44 which may `be conveniently mounted on the rod support 36 and the handle member 42 controls the valve as will be seen from the diagrammatic View in FIG. 4. The valve 44 comprises in general a cylinder having a `double-ended piston member 46, 4S, connected by means of a member Sd which is bored from end-to-end so that the ends of the cylinder as at 52 and 54 communicate with each other.

When the rod 42 is in neutral position, the valve mem-- bers 46 and 48 completely cover ports 56 and 58. There is a constant pressure applied through a port at 60. This pressure may `be obtained in any convenient way as by means of a conventional pump generally indicated at 62,

the same being conveniently driven from motor 2t?. OtherY requisite means may also be provided such as the tank 64 and appropriate piping, etc. The ports 56 and 58 are connected to `opposite ends of a ram generally indicated at 66 and comprising a cylinder mounted on the framework of the bench 16 and having a piston and piston rod 63 extending to and connected to the standard 24 by which means the ram 66 moves the yentire standard and the tool forward and backward on the rock shaft in the block 22. If desired, a balance spring 70 may be used to hold the tool 34 in its uppermost inoperative position as easily seen in FIG. 1.

When the operator grasps the handle 40, thus moving rod 42 slightly forwardly, pressure entering port 60 will.

then travel through the slightly open port 56 to the lefthand end of cylinder 66 as seen in FIG. 4, thus moving the piston therein forwardly and moving the entire rocking or swinging tool forwardly at a controlled rate of speed. It is to be understood that although the motion of the rod 42 is limited to a relatively small travel, nevertheless by means of balance springs 72 within cylinder 44, the operation or travel of the ltool 34 is controlled very accurately so that the ports at 56 and 58 may be opened a relatively small amount for slow travel of the tool 34 in either direction, and they may Abe opened to.

greater degrees in order to provide for faster travel in corresponding degree. When the operator wishes to retract the tool, he merely pushes the handle to the rear. The pressure in both ends of the cylinder comprising the valve 44 is the same land this applies the pressure then to the opposite end of cylinder 66, causing a controlled single speed retraction of the entire device as long as the operator keeps the handle in this position, i.e., by pushing slightly backwardly on it. Cylinder 66 exhausts from both yends at the opposite port 56 or 58, depending upon which one is admitting pressure. Exhaust back to the tank is provided in the center of the valve 44 by means of the exhaust port at 73.

It will be seen that this invention provides in a swinging tool mechanism a controlled forward and reverse feed under the control of the operator at all times by a natural motion in the actuation of the machine in order to carry out its intended function; and no matter how hard the buliing tool or other tool is applied to the work, there will be no vclimb or unwanted progress of the tool due to the friction encountered between the tool and the work, and therefore the operator may carry out his operation quickly and easily and a great deal safer than with swing ytools which are not controlled by power means such as is presented by'the present invention. Particularly it is to be noted that the operator need only direct his attention to the work he is doing and need not consider with how much pressure he pulls the tool. In prior art devices of the class described, the operator must exert some skill in balancing the tool pressure on the Work with the unwanted forward progress or rearward progress as the case may be, depending upon rotation of the tool.

One of the advantageous eiects of this invention resides in the complete ease lof control not only of the tool but also of the work which is clamped on the rotary table 10. By this means, it will be seen that the operator by either foot or hand controls, can reposition the work almost instantly while at the same time the tool is moved by power out of contact with the work. Thus odd shaped pieces may be quickly polished by power controlled operations both as to indexing of the work, rectilinearly and rotatably, and by the power occasioned travel of the tool backwards and forwards. As a matter of fact, shapes may be polished which may be done in no other way except by the old method of holding the piece of work in the hand and pushing it up to engagement with the stationary lbuff. Hence it is seen that the combination of the work-holding means and the tool is an extremely effective device for the quick, easy and accurate polishing of workpieces which could not be done in the prior art in any Way except by a very skilled polisher, and the new invention provides for the action to be done better and much faster.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. A device of the class described comprising a base, a standard swingably mounted thereon, a second swinging member on said standard, a tool on said second swinging member, a handle adjacent said tool, said handle being slightly movable relative to said second swinging member and said tool, a valve on said second swinging member, a connection from the handle to the valve, a hydraulic cylinder mounted on said base, a piston and piston rod for said hydraulic cylinder connected to the standard and causing the same and with it the second swinging member to move in a swinging motion when actuated by the valve.

2. The device as recited in claim 1 wherein said valve comprises a balanced double-ended reciprocal valve connection and said valve 'being directly connected to said handle, a source of pressure at each end of said valve, one end of said cylinder being provided with pressure, de-

- pending upon the direction of actuation of said valve, and

the other end of the cylinder acting as an exhaust.

3. The combination of a swingable standard, a tool on said standard for travel in a working path, a support,

. a work-holding member on said support, said work-holding member being mounted for combined rectilinear and rotary motion relative to said tool, the work holding member being rotatably mounted on an axis generally at right angles to the path of the tool, the path of said tool extending across the work-holding member, power means for traveling said tool relative to the work, said workholding member and said tool being under the control of the operator at all ti-mes whereby the work-holding member may be shifted for a new stroke of the tool when the tool is retracted, the means for traveling said tool comprising a hydraulic cylinder, a piston and piston rod for the cylinder, said piston rod being connected to said standard for causing the same to swing, a valve and means under the control of the operator for operating said valve, said valve controlling the hydraulic piston in the reciprocal motion thereof.

4. The combination of a universally mounted workholding table and a swinging bufting tool, said swinging bufling tool comprising a rst standard mounted generally vertically to swing in Aa vertical plane and a second standard mounted generally horizontally at the upper end of the first standard, means mounting the second standard for swinging motion relative to the rst standard, a buiing tool on said second standard, power means for moving the first standard on its aXis to bring the buing tool across the said work-holding table, and means located adjacent said buing tool and under the control of the operator for controlling said power means.

5. The combination of claim 4 wherein the operator controlled means includes a handle mounted adjacent the buing tool and in position to be grasped by the operator, and the control means being actuated by the said handle, said handle being movable relative to said second standard in order to accomplish the controlling function.

6. The combination of claim 4 wherein the operator controlled means for the power means includes a handle adjacent the buing tool, a valve, said handle being connected to said valve for actuating the same forwardly and rearwardly, and wherein said power means includes a cylinder, and a piston rod therefor, said piston rod being connected to the rst standard for moving the same on itsV axis, said second standard being generally free to move up and down under the control of the operator.

7. The combination of claim 4 wherein the operator controlled means for the power means includes a handle adjacent the buiiing tool, a valve, said handle Abeing connected to said valve for actuating the same forwardly and rearwardly, and wherein said power means includes a cylinder, and a piston rod therefor, said piston rod being connected to the first standard for moving the same on its axis, said second standard being generally free to move up and down under the control of the operator, and means balancing said second standard to maintain the bufdng tool in Aa position above the work-holding table.

Copp Nov. 4, 1879 Gurney Mar. 1.0, 1959 

